code: def test_results(self):
      x = torch.Tensor([[1, 2], [1, 2], [1, 2]])
      y = torch.Tensor([[2, 2], [1, 2], [1, 2]])
      results = FIDMetric()(x, y)
      np.testing.assert_allclose(
          results.cpu().numpy(), 0.4444, atol=1e-4
      )
  
file_path: MONAI/tests/test_compute_fid_metric.py
imports: from __future__ import annotations
  import unittest
  import numpy
  import torch
  from monai.metrics import FIDMetric
  from monai.utils import optional_import
label_desc: Use image node_id 1 for calling the TestFIDMetric obj's underlying member method code with example usage: obj.test_results() without return types